In the treatment of sleep disordered breathing, a patient receives a supply of air or breathable gas at positive pressure to “splint” open their airway. The supply of air or gas is delivered to the patient via a patient interface, such as a facial mask. The patient interface is typically held in position by headgear. Headgear typically includes a number of straps that in use are attached to the patient interface at an anchor point. In use, the various straps are tightened to secure the mask in position and to prevent it from lifting off the face under pressure. Generally, the higher the treatment pressure, the tighter the mask strap needs to be. When poorly fitting masks are used, patients sometimes over tighten the straps to try to get a seal. This can lead to pressure sores on their face. It is a continuing challenge for designers and manufacturers to provide a patient interface with comfortable seal against leak.
The addition of a forehead support to a facial mask can assist in stabilising the mask and provide a convenient means to adjust the mask to suit each patient. Improving the fit of the mask can lead to improved comfort, reduced noise and a more effective therapy.
Other known arrangements are found in U.S. Pat. Nos. 6,422,238 and 6,536,435 and Australian Patent Application AU 200071882 A1.